Pyrrocoma is a genus of perennial wildflowers in the family Asteraceae (order Asterales), native to western North America, where they grow across a wide range of habitats from alpine zones to grasslands and shrublands. The genus is commonly known as goldenweeds. Plants are characterized by reddish stems and yellow, daisy-like flower heads typical of the aster family.
The species now placed in Pyrrocoma were previously treated as members of the large, heterogeneous genus Haplopappus, but have since been segregated into their own genus on the basis of morphological and phylogenetic evidence. The genus comprises roughly 15 species distributed across the western United States and adjacent Canada, with individual species ranging from British Columbia and the Prairie provinces south through the Rocky Mountain states, Great Basin, and Pacific Coast states to Texas, Arizona, and New Mexico.
Notable members include Pyrrocoma carthamoides (largeflower goldenweed), one of the most widespread species ranging from British Columbia to California and Wyoming; Pyrrocoma lanceolata (lanceleaf goldenweed), which has the broadest distribution of the genus, reaching from Manitoba south to Texas; and Pyrrocoma apargioides (alpineflames), an alpine specialist of California, Nevada, and Utah.
Distribution
Pyrrocoma is native to western North America. The genus ranges from British Columbia, Alberta, Saskatchewan, and Manitoba in Canada south through the Pacific Coast states (Washington, Oregon, California), the Rocky Mountain states (Montana, Idaho, Wyoming, Colorado, Utah, Nevada), and into the southwestern United States (Arizona, New Mexico) and as far east as Texas. Different species occupy distinct elevational and geographic niches within this overall range, from alpine meadows to lower-elevation grasslands and shrublands.
Taxonomy Notes
Pyrrocoma species were formerly included in the broad genus Haplopappus (family Asteraceae). They were later recognized as a distinct genus based on morphological characteristics including their perennial habit, reddish stems, and the structure of their yellow ray-and-disc flower heads. GBIF accepts Pyrrocoma at genus rank within Asteraceae, order Asterales.
